4-coloring ($P_6$, bull)-free graphs

Frédéric Maffray; Lucas Pastor

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arXiv · 1511.08911

4-coloring ($P_6$, bull)-free graphs

Frédéric Maffray·Lucas Pastor

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Abstract

We present a polynomial-time algorithm that determines whether a graph that contains no induced path on six vertices and no bull (the graph with vertices a, b, c, d, e and edges ab, bc, cd, be, ce) is 4-colorable. We also show that for any fixed k the k-coloring problem can be solved in polynomial time in the class of ($P_6$, bull, gem)-free graphs.

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Frédéric Maffray, Lucas Pastor. 2016-02-24. 4-coloring ($P_6$, bull)-free graphs. https://arxiv.org/abs/1511.08911

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